http://onemileatatime.boardingarea.c...lass-seat-787/

People have reported that the seats that are connected shake. I’ve had them shake a bit, but it’s barely noticeable, and it definitely didn’t hurt my sleep at all on a 15 hour flight to Shanghai. So I wouldn’t be too concerned about which seat you choose. It’s really just a matter of whether or not you prefer the forward facing or the backward facing.